1. Field of the Invention
The present invention relates to a method for resetting a CMOS imaging element in an endoscope apparatus, and more particularly, to a method for resetting a CMOS imaging element in an endoscope apparatus where a CMOS imaging element which takes an endoscope image is used at the distal end of an endoscope insertion portion.
2. Description of the Related Art
Examination using an endoscope apparatus, for example, an electronic endoscope has been quite popular in the medical field. In the electronic endoscope, an image sensor such as a CCD sensor and a CMOS sensor is mounted at the distal end of an insertion portion to be inserted into a subject, and is connected to a processor apparatus (a signal processing apparatus) through a cord or a connector. The processor apparatus performs various processing on an imaging signal obtained from the image sensor, and generates an endoscope image for use in diagnosis. The endoscope image is displayed on a monitor connected to the processor apparatus.
CCD sensors have been generally used as the image sensor provided at the endoscope insertion portion. However, the use of CMOS sensors has been considered recently (for example, see Japanese Patent Application Laid-Open No. 2009-201540). The CMOS sensors are different from the CCD sensors, and can be formed as a CMOS imaging element by a general CMOS manufacturing process on the same chip as peripheral circuits such as a signal processing circuit, a timing generator, an A/D converter, and a communication interface.